since KDE4 is in unstable, the taskbar behaves very annoyingly when
working with two monitors with different resolutions. I have a laptop.
When I'm at work, I put it into a docking station which is connected to
a huge monitor. I'm not working with dualhead or something, I'm just
using the huge monitor at work and the laptop's screen at home.

I always want the taskbar to be maximized. The problem is, that KDE's
taskbar fails to adjust the size of the taskbar correctly: Starting KDE
at work, the taskbar is always too small (as wide as the laptop's
monitor) and my first task is to maximize the taskbar. Starting KDE when
I'm back home, the taskbar is too wide (as wide as the external
monitor's size) for the smaller monitor and I have to (ironically)
maximize it again to fit on the now smaller monitor.

Note that I'm not using suspend or something. I'm booting the laptop
with the big screen connected or not.

I also had that problem with KDE3, but that was fixed upstream long time
ago. Has anyone a solution how to avoid this problem?